Kconfig: Rename CONFIG_SPL_DMA_SUPPORT to CONFIG_SPL_DMA

Rename CONFIG_SPL_DMA_SUPPORT to CONFIG_SPL_DMA. This allows to use
macros such as CONFIG_IS_ENABLED() that allow conditional compilation of
code for SPL and U-Boot.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/Makefile b/drivers/Makefile
index e7b5d22..23501fd 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -45,7 +45,7 @@
 obj-$(CONFIG_SPL_POWER_SUPPORT) += power/regulator/
 obj-$(CONFIG_SPL_POWER_DOMAIN) += power/domain/
 obj-$(CONFIG_SPL_DM_RESET) += reset/
-obj-$(CONFIG_SPL_DMA_SUPPORT) += dma/
+obj-$(CONFIG_SPL_DMA) += dma/
 obj-$(CONFIG_SPL_ETH_SUPPORT) += net/
 obj-$(CONFIG_SPL_ETH_SUPPORT) += net/phy/
 obj-$(CONFIG_SPL_USB_ETHER) += net/phy/